In the steel industry, a so-called "C" hook is used to lift and transport steel coils. The hook is usually made from steel plate and, as the name implies, is generally C-shaped in configuration, having a vertical portion with upper and lower horizontal legs projecting therefrom. The horizontal upper leg has a clevis attached to the "C" hook at its approximate center or balance point such that a crane hook may be inserted into the clevis for lifting. The bottom leg of the hook is inserted into the central opening of a steel coil such that when the hook is lifted by a crane, it will carry with it the coil which rests on the lower leg.
As can be understood, the lower leg of the "C" hook is inserted into the central opening of coil while suspended from an overhead crane. The hook is typically formed from about three inch steel plate and, consequently, is quite heavy. It often happens that the vertical portion of the hook slams against the side of the coil while the vertical leg is being introduced into the central opening of the coil. This can cause damage to the edges of the strip material, even though the edges might be perfectly aligned.